Actually, let me go ahead and bring my friend in here for more feedback, just to make sure I'm not missing anything on the LM side of the match. (@
LCC Son-in-Law
)
IMO the main thing Luigi has problems with in the Little Mac match up (and stay with me on this) is his edge guarding ability. It is INSANELY hard to get back on stage from the ledge vs a solid LM. He just has so many coverage options and with a decent amount of prediction and reaction, LM is fast enough to automatically react to what you're doing when it comes to rolling back on. Mixing up your recovery options is extremely essential. Also...
1) Watch out for LM's down tilt. It pops you in the air and combos into almost anything. This is especially scary on Halberd with the stage sinking down into the middle. LM can camp the slight incline and hit you with a pretty easy d-tilt when you try to approach. My friend caught me off guard with that one. I'm convinced Halberd is an awesome stage for LM.
2) Obviously super armor is a major problem. LM's moves come out super quick and hit super hard. Try not to challenge an f-smash/f-tilt too often unless you have a guaranteed connect on a grab.
3) Run up -> up smash is too good. My friend gets me with the sweet spot on this constantly when I'm landing (RIP Luigi's air speed) and it hits SO hard.
4) Don't feel too safe on higher ledges and platforms. Up b is a very good mix-up option for them, and I've been killed off of the top of battlefield because I got cocky on the top platform
5) A wise LM knows how to distract you, but also play keep away when he gets his KO punch. One fireball is enough to make that thing disappear, so wait it out for a few seconds and make sure you're spaced well. Don't go in head first, but don't just stand there. Try to bait out the punch, but keep your distance.
6) DO NOT constantly go for extra chops off stage. I've been caught off guard several times by getting n-air -> footstool gimped after a d-throw -> x3 fair combo off stage. I definitely learned the hard way haha.
Honestly, I think this is a pretty even match. I might even go so far as to say it's in Luigi's favor.
Fireballs are always good to approach with, because LM can't do too much about projectile game besides force you up close with speed. However, patience and reaction are key with them, as going in head strong will just result in being thrown off stage constantly.
Keep in mind that if you DO throw them off stage and they shoot for an up-b recovery below the stage, it can be hard to sweet spot and it sometimes leaves them open for a multitude of things, including (but not limited to) a d-tilt, d-smash, or even a taunt spike if you want to be stylish. However, it's not the easiest thing to pull off due to the hitbox on his up-b. I've also occasionally gotten jab -> grab out of it.
Grounded 'nado is, as always, a good mix-up option for us. It's hard to deal with and not many things beat it.
I have not tested whether d-throw -> x2 fair -> fast fall (maybe n-air) -> x4-5 up tilt works against LM, but due to weight and fall speed, I'm pretty sure it would. If so, this would be very good to quickly get in % range for any variety of kill moves.
I also think that LM is fairly easy to hit with the d-throw -> up b combo due to his lack of aerial mobility.
EDIT: I forgot the summary. Oops.
Summary: While LM has an amazing ground game, tons of move priority, and quite a lot of options near the edge, I believe that they come out pretty even. LM can't do much in terms of getting out of throw combos on stage. He also has trouble approaching against fireballs, and resorts to a lot of shielding which is easy to follow up with a grab if spaced right. As long as you don't get cocky, I'd say this match comes out to 50/50, or possibly even 55/45.
Hopefully I didn't miss anything! Let me know if there are any particular things you have trouble with in the match-up that I didn't cover.